Midway up the final scramble of the unofficial Mount Tam Hill Climb, with lungs burning and quads screaming, nobody’s thinking about evaporative heat loss or air permeability. The Fore Runner takes care of it, thanks to an ultralight, highly breathable and fast-wicking 100% polyester fabric. Meanwhile, flatlock seams (offset at shoulder) provide no-chafe, next-to-skin comfort, and a locker loop lets you dry it out afterward. The running shirt’s updated sleeve design is now more streamlined, with a range-of-motion-enhancing underarm gusset that comes in handy at the finish line–when you reach up and touch the door of the Tamalpais lookout tower. With 15-UPF sun protection, Polygiene® permanent odor control and reflective logos on the chest and center back neck.

Odor Resistant

Polygiene® odor control permanently protects your garments from smelling like a middle school locker room. Sweat itself is odorless, but it creates the conditions that bacteria need to multiply, and some of those bacteria produce odors. Polygiene permanent odor control stops the growth of odor-causing bacteria on fabrics, so you can wear more and wash less.

Active only on the fabric surface, Polygiene permanent odor control does not interfere with perspiration or with the skin’s natural bacterial flora. Polygiene particles are more than 100 times larger than nanoparticles and therefore are too large to penetrate to the skin’s barrier. Polygiene-treated fabrics have received Medical Class 1 approval in Europe, the same class that includes bandages.

Sun Protection

Lacking fur, feathers or scales, we humans have to think up clever ways to protect ourselves from the sun. Products with the UPF designation provide built-in sun protection that won’t wear off.

UPF stands for “Ultraviolet Protection Factor.” This value represents the fractional amount of the sun’s harmful UV rays that pass through a fabric. A rating of “25” indicates that only 1/25th , or 4% of the UV rays pass through the garment.

Patagonia products with rated UPF protection are tested independently to meet Australia/New Zealand or AATCC protocols. A rating of 15-24 earns a product a rating of “good”; a rating of 25-39 is "very good"; and a rating of 40-50+ is “excellent.” *

Measurements refer to body size, not garment dimensions, and are in inches, unless otherwise noted.* Inseam will vary depending on style; when lengths are offered, "short" is 30, "regular" is 32 and "long" is 34, unless otherwise noted.

XX-Small

Chest

31-33

Neck

13 1/2-14

Sleeve

31

Waist

26

Inseam*

30

Women's Conversion Size

-

X-Small

Chest

34-35

Neck

14-14 1/2

Sleeve

32

Waist

28

Inseam*

31

Women's Conversion Size

4-6

Small

Chest

36-38

Neck

15-15 1/2

Sleeve

33

Waist

29-30

Inseam*

31

Women's Conversion Size

8-10

Medium

Chest

38-40

Neck

15 1/2-16

Sleeve

34

Waist

31-33

Inseam*

32

Women's Conversion Size

12-14

Large

Chest

42-44

Neck

16 1/2-17

Sleeve

35

Waist

34-36

Inseam*

33

Women's Conversion Size

14-16

X-Large

Chest

46-48

Neck

17-17 1/2

Sleeve

36

Waist

38-40

Inseam*

33

Women's Conversion Size

-

XX-Large

Chest

50-52

Neck

17 1/2-18

Sleeve

37

Waist

42-44

Inseam*

33

Women's Conversion Size

-

XXX-Large

Chest

54-56

Neck

18 1/2

Sleeve

38

Waist

46-48

Inseam*

33

Women's Conversion Size

-

Measurements refer to body size, not garment dimensions, and are in inches, unless otherwise noted.* Inseam will vary depending on style; when lengths are offered, "short" is 30, "regular" is 32 and "long" is 33, unless otherwise noted.

Men's Fit Guide

Though each Patagonia® product is designed and shaped specifically for its intended use, we can generalize our fit descriptions in four ways: